Page:Philosophical Transactions - Volume 002.djvu/196

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here, as far as the numerous bubbles excited in the Water would give us leave to discern it (for they did, though not unexpectedly somewhat disturb the Experiment, which inconvenience we might have prevented, if we had thought it worth while) we could not perceive, that either the absence or return of the Air had any great operation upon the Light of the immersed Body; which yet did not keep me from intending to make a somewhat like Trial with Shining Wood (when I can get any) fastened to the lower part of a clear Glass, and covered over, but not very deep, with Quicksilver. Of which practice I shall not now stay to give you the Reasons, having elsewhere fully enough expressed them.

And that this Section may acquaint you with something besides the (seemingly) insignificant Experiment related in it, I shall here inform you (since I perceive, I did not in the first Papers I sent you) that though, when I formerly put together some Notes about Luminous Bodies, I confined not my Observations to one or two sorts of Fishes, yet the Experiments, sent you since October last, were all of them (except a Collateral one or two) made with Whitings, which, among the Fishes, I have had occasion to take notice of, is (except one sort that I cannot procure) the fittest for such Trials, and consequently fit to be named to you, to facilitate your future ones, in case you think it requisite to make any upon such subjects.

Experiment XV.

The other of the two neighbouring Experiments I lately mention'd (viz. the ninth) I told you, when I sent it you, needed a reiteration to confirm it, since we had but once tried it (and that without all the convenience we desired) that a shining Body, which upon the first withdrawing the Air loseth much, but not all its Light, may be deprived of the rest by continuing in that unfriendly place, though the Air be no further exhausted. To prosecute, therefore both the Experiments in one Trial, we took somewhat late at night a piece of rotten Fish, which we judged to shine too strongly, to be quickly deprived of all its Light, and having put it into a small and clear Receiver, we found (as we had foreseen) that the Light was much impaired, but nothing near

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